Dexamethasone

Dexamethasone

Pregnancy Category C

Drug classes: Corticosteroid, Glucocorticoid, Hormone

 

Therapeutic actions

Enters target cells and binds to specific receptors, initiating many complex reactions that are responsible for its antiinflammatory and immunosuppressive effects.

 

Indications

· Hypercalcemia associated with cancer

· Short-term management of various inflammatory and allergic disorders, such as rheumatoid arthritis, collagen diseases (SLE), dermatologic diseases (pemphigus), status asthmaticus, and autoimmune disorders

· Hematologic disorders: thrombocytopenic purpura, erythroblastopenia

· Trichinosis with neurologic or myocardial involvement

· Ulcerative colitis, acute exacerbations of multiple sclerosis, and palliation in some leukemias and lymphomas

· Cerebral edema associated with brain tumor, craniotomy, or head injury

· Testing adrenocortical hyperfunction

· Unlabeled uses: Antiemetic for cisplatin-induced vomiting, diagnosis of depression

· Intra-articular or soft-tissue administration: Arthritis, psoriatic plaques

· Respiratory inhalant: Control of bronchial asthma requiring corticosteroids in conjunction with other therapy

· Intranasal: Relief of symptoms of seasonal or perennial rhinitis that responds poorly to other treatments

· Dermatologic preparations: Relief of inflammatory and pruritic manifestations of dermatoses that are steroid-responsive

· Ophthalmic preparations: Inflammation of the lid, conjunctiva, cornea, and globe

 

Contraindications

· Contraindicated with infections, especially tuberculosis, fungal infections, amebiasis, vaccinia and varicella, and antibiotic-resistant infections.

 

Adverse effects

Adverse effects depend on dose, route, and duration of therapy. The first list is primarily associated with absorption; the list following is related to specific routes of administration.

Convulsions, vertigo, headaches, pseudotumor cerebri, euphoria, insomnia, mood swings, depression, psychosis, intracerebral hemorrhage, reversible cerebral atrophy in infants, cataracts, increased intraocular pressure, glaucoma

Hypertension, CHF, necrotizing angiitis

Growth retardation, decreased carbohydrate tolerance, diabetes mellitus, cushingoid state, secondary adrenocortical and pituitary unresponsiveness

Peptic or esophageal ulcer, pancreatitis, abdominal distention

Amenorrhea, irregular menses

Fluid and electrolyte disturbances, negative nitrogen balance, increased blood sugar, glycosuria, increased serum cholesterol, decreased serum T₃ and T₄ levels

Anaphylactoid or hypersensitivity reactions

Muscle weakness, steroid myopathy, loss of muscle mass, osteoporosis, spontaneous fractures

Impaired wound healing; petechiae; ecchymoses; increased sweating; thin and fragile skin; acne; immunosuppression and masking of signs of infection; activation of latent infections, including tuberculosis, fungal, and viral eye infections; pneumonia; abscess; septic infection; GI and GU infections

 

Drug Interactions:

· Increased therapeutic and toxic effects of dexamethasone with troleandomycin

· Decreased effects of anticholinesterases with corticotropin; profound muscular depression is possible

· Decreased steroid blood levels with phenytoin, phenobarbital, rifampin

· Decreased serum levels of salicylates with dexamethasone

Interactions with lab-test:

· False-negative nitroblue-tetrazolium test for bacterial infection

· Suppression of skin test reactions

 

Nursing considerations

· For systemic administration: Do not give drug to nursing mothers; drug is secreted in breast milk.

· Give daily doses before 9 AM to mimic normal peak corticosteroid blood levels.

· Increase dosage when patient is subject to stress.

· Taper doses when discontinuing high-dose or long-term therapy.

· Do not give live virus vaccines with immunosuppressive doses of corticosteroids.

· For respiratory inhalant, intranasal preparation: Do not use respiratory inhalant during an acute asthmatic attack or to manage status asthmaticus.

· Do not use intranasal product with untreated local nasal infections, epistaxis, nasal trauma, septal ulcers, or recent nasal surgery.

· Taper systemic steroids carefully during transfer to inhalational steroids; adrenal insufficiency deaths have occurred.

· For topical dermatologic preparations: Use caution when occlusive dressings, tight diapers cover affected area; these can increase systemic absorption.

· Avoid prolonged use near the eyes, in genital and rectal areas, and in skin creases.